Over 85% of women suffer obstetric trauma to one or several components of the pelvic floor, with vagina, perineal body, levator ani muscles, and the anal sphincter complex affected most commonly. Birth injury to these integral structural components of the female pelvic floor leads to pelvic pain and dyspareunia, and serves as the most important and potentially modifiable risk factor for subsequent pelvic floor disorders. Unfortunately, there are currently no preventive strategies beyond elective Cesarean delivery, which is associated with many untoward consequences. Our central thesis that pelvic tissues? biomechanical properties in late pregnancy determine the risk of birth injury for a set of specific intrapartum conditions, i.e. fetal head size, shape/size of maternal bony pelvis, duration of expulsive efforts. The long-term goal of this project to develop, validate and integrate into clinical practice a novel device, Antepartum Tactile Imager (ATI), to simultaneously measure biomechanical properties of various pelvic structural components that are impacted during vaginal delivery, and to develop a risk prediction model of maternal birth injury by correlating ATI data with postpartum outcomes. Ultimately, such model will enable individualized patient counseling regarding the mode of delivery and/or the need for obstetrical interventions to reduce childbirth trauma. Phase I Specific Aims target to design ATI ?-prototype and explore imaging quality, examination technique, probe design and safety in a pilot clinical study of non-pregnant and pregnant women.